This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Centrosomes are the primary microtubule organizing centers in animal cells. Our laboratory is interested in determining how centrosomes assemble and function, using C. elegans as a model. Previous work in a number of laboratories has identified ~15 proteins required for centrosome function in this organism. We are currently using biochemistry to further characterize these proteins and identify additional proteins by virtue of their interaction with known centrosomal proteins.